1. Field of Invention
The present invention relates to a form, fill, and seal machine and a method for producing, filling, and closing bags.
2. Description of the Prior Art
Machines of this type are known from the prior art and are used in various sectors of technology. These machines are used to “Form,” “Fill,” and “Seal” bags. The term FFS for “Form, Fill, and Seal machine” has thus also made way into the German language area with reference to these machines.
Efficient and automated versions of these machines, in particular, unwind a plastic tube from an unwinding station, perform a cross-welding process on the same, separate the tube provided with cross-welding to form bags (=tube piece with cross-welding), open the bag, fill the bag with a filling pipe comprising fill material, close the bag, provide the sealed bag opening with another cross-welding sealing the bag, and place the finished, filled bag on a suitable pallet or a transport means such as a conveyor belt.
Independent processing stations are often assigned to each of or at least a plurality of the processing steps mentioned above. Suitable transport means are to be provided in this case. If the unwinding process is considered to be a processing station, then the transport means, using which the tube is brought from the unwinding station to the cross-welding and separating station, usually comprise typical tube-transporting means such as guide rollers. Following the separation of the bags, relatively more nonstandard transport means, which usually comprise gripping means, are required since the bags, as a rule, are to be grasped at their ends, still open, and transported. The sealed end of the bag usually hangs down. Individual grippers or pairs of grippers are usually used as gripping means.
A machine of this type has been disclosed in EP 1 201 539 B1 for example. The manner, in which bags or semi-finished goods are transported or produced in the machine illustrated in this document, the sequence of the individual processing stations and the manner, in which bags are produced, filled, and sealed in this machine, are essential for understanding the present document and are incorporated by reference herein.
Reduction of the maintenance and operating costs of a machine of this type is an ever-persisting task of the machine designer and also forms the basis of the present invention.
It has been shown that the ability to operate and maintain a machine of this type comprising linearly successively disposed processing stations can be expanded.